Re: [Tagging] Spillways

[John Willis]

> On Mar 25, 2017, at 12:54 AM, Richard  wrote:
> 
> This would include most 
> levees even if we usualy don't map them explicitly.

We have a dyke tag because the levees do not block the flow of the river. They 
prevent it from flooding out of the path the river is already flowing. 

In this system, except for two-three gates (about 50m total), nothing 
explicitly is built "across" the river. They contain it. 

They built this weird thing out of levees, rather than putting a big gravity 
dam across the river and making a traditional big reservoir. 

This whole thing is built like a radiator's overflow reservoir. It only takes 
in water when the river flows over the weirs in the sides of the levees. The 
river always continues, without hinderance, without passing through a weir or a 
gate, to meet the larger river. There is no dam. 
Only the surge that overflows at the narrowing part is captured and slowed 
down. 

I admit, this is weird, and the gates at the bottom of the reservoir could be 
considered a dam, but it is actually a whole lot of levees. 

Javbw. 
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Re: [Tagging] Spillways

[Richard]

On Fri, Mar 24, 2017 at 09:42:35AM +0900, John Willis wrote:
> 
> The thing I am tagging is not a dam. It is a series of flood basins, one of 
> which is a "reservoir". They are made by levees that surround the rivers, but 
> in a very complicated way. They eventually return all the water back to the 
> river, shortly after it is captured. 
> 
> I explain that below, if you are interested, 
> 
> But the TL;DR is that it is a weird combination of levees, weirs, spillways, 
> gates (which are possibly considered a dam), channels, valves, and other 
> things that are not properly fleshed out in OSM, and they should have tags 
> created/expanded for them. 

well I was asking because for me any kind of artificial wall designed to impound
water is a waterway=dam (or weir if water runs over it). This would include 
most 
levees even if we usualy don't map them explicitly.
They could be mapped as embankment but if you consider waterway=dam inadequate 
for
it I would prefer a special levee tag or refining waterway=dam with additional 
attributes.

The waterway=dam definition is showing age and could use some refinement
anyway.

Richard

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Re: [Tagging] Spillways

[Lorenzo "Beba" Beltrami]

2017-03-24 1:42 GMT+01:00 John Willis :

>
> The thing I am tagging is not a dam. It is a series of flood basins, one
> of which is a "reservoir". They are made by levees that surround the
> rivers, but in a very complicated way. They eventually return all the water
> back to the river, shortly after it is captured.
>

I had the same problem here in the Po valley[1].
In the whole Po valley there are very complicated systems of levees to
manage the river floods.

Months ago we started a discussion here[2] that led only to few
considerations.

Lorenzo

[1] https://en.wikipedia.org/wiki/Po_Valley
[2] https://lists.openstreetmap.org/pipermail/tagging/2016-
November/030693.html
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Re: [Tagging] Spillways

[John Willis]

> On Mar 24, 2017, at 9:42 AM, John Willis  wrote:
> 
> The thing I am tagging is not a dam. It is a series of flood basins, one of 
> which is a "reservoir". They are made by levees that surround the rivers, but 
> in a very complicated way. They eventually return all the water back to the 
> river, shortly after it is captured. 

I made a quick way around the entire extent of the feature. It is really big. 

https://www.openstreetmap.org/way/482421468#map=13/36.2357/139.6842 


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Re: [Tagging] Spillways

[John Willis]

The thing I am tagging is not a dam. It is a series of flood basins, one of 
which is a "reservoir". They are made by levees that surround the rivers, but 
in a very complicated way. They eventually return all the water back to the 
river, shortly after it is captured. 

I explain that below, if you are interested, 

But the TL;DR is that it is a weird combination of levees, weirs, spillways, 
gates (which are possibly considered a dam), channels, valves, and other things 
that are not properly fleshed out in OSM, and they should have tags 
created/expanded for them. 



On Mar 24, 2017, at 7:34 AM, Richard  wrote:

>> earthen embankment (levee) around the entire river system - it is part of 
>> that. 
> 
> this is still a dam for me?

This thing I am tagging is really weird. 

Japan is full of massive gravity dams that catch storm water and snow melt to 
from giant lakes. Canyons has flow blocking "dams" with weirs in the center to 
stop flash floods. 

This thing is like something I have never seen. It is like 10x 6 km of man made 
structures nested together. 

It is a "retardation basin" for a smaller river feeding into a larger river. 

The system is not for water storage, it is temporary surge overflow for the 
river. 

Here is the river where it meets the flood plain, after the typhoon surge in 
the middle of the night. Note, this is completely contained in levees from this 
point where it leaves this mountain to where it empties into the pacific ~ 
160km later, as it crosses above Tokyo. 

https://m.flickr.com/#/photos/javbw/11091304694/sizes/o/

The brown river on the left is about 5x normal flow at this point, down 3m in 
height from the surge the night before, which would exceed 10x. 

It is heading down to this thing I am tagging, off in the haze. The ghostly 
river in the upper right will take the water from it afterward.

This "retardation system" forces that surge  water into a series of basins 
connected by channels that automatically empty themselves. Due to the basin's 
entrance being much larger than it's exit, a typhoon surge on this smaller 
river is caught and dissipated, while normally (350 days a year?) the river is 
5-7m lower than the entrance to the system, and is unused. 

The system is made of levees, with small control gates at the bottom. These 
small gates would be the "dam" - the levees wrap around this thing, like a golf 
ball inside a snake. 

Above this retardation system, the levees narrow the river basin from 200m wide 
to less than 50m. On either side, the narrowing section has 10m embankments 
with 500m long weirs that empty into both a small and a very large open basin 
that used to be swamps. 

The large open basin has an additional levee system around a series of 3 
successively larger "reservoirs" inside it. This inter basin is tagged as a 
reservoir, and has a little rarer year round, fed by a couple tiny streams year 
round through small culverts (with control valves big and small) in the levee 
embankment. 

 Gated channels direct water from the large outer basin to the inner basins 
that look like a heart. There is an 1km additional spillway in the inter basin 
to let water rapidly in or out  the inner basin as well. Below this spillway is 
a road in the outer basin, dry and drivable most of the year. 

Having the outer basin catch a surge from a typhoon on this tributary gives the 
system downstream a chance to deal with the surge from the main river first. 

The bottom of the inner basin has flow control gates to empty it back into the 
outer basin. This very tiny (50m?) section would be the dam. 

The water then flows into the end of the outer basin, through another set of 
control gates, back into the river all the water came from to begin with. There 
is another 1km long spillway that connects the outer basin to the river. This 
is the one I marked with an area.  

Being able to tag levees, control flow valves for drains and streams that empty 
into the inner basin, the gates for the "dam" the spillways and weirs by area, 
are all currently deficient in OSM. 

Wrapping the inner and outer basins completely in a circular shaped dam inside 
another circular dam is avoiding properly fleshing out the tagging of large, 
detailed, and complex man-made water control systems. 

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Re: [Tagging] Spillways

[Warin]

On 24-Mar-17 03:51 AM, Tobias Wrede wrote:

Hello,

actually, I have used
   warterway=spillway
   intermittent=yes
in the past, reasoning that this particular spillway 
(http://www.openstreetmap.org/way/451309286) is rarely put to use, 
while others might be more permanently flooded (regularly during high 
tides for example)


Tobias

Am 23.03.2017 um 12:58 schrieb John Sturdy:
I suppose  waterway=weir plus intermittent=yes would describe it, but 
I don't think that's as good as a specific spillway tag.


On Thu, Mar 23, 2017 at 6:52 AM, Andrew Harvey 
> wrote:


On 22 March 2017 at 16:56, Dave Swarthout
> wrote:
> Weir does not seem appropriate for this type of thing. There is
a tag,
> waterway=spillway, that seems like a good fit - 81 uses so far.

I've seen these tagged as waterway=drain which is close but agree
that
waterway=spillway is better. Would be great to have this
documented on
the wiki.




There is at least one 'spillway' that is a pipe in the lake ... shaped 
like a funnel for flow ... but it is not your traditional 'spillway' in 
that it does not go over the wall but under.
In that case 'drain' is a more appropriate word... but the function is 
still a spillway.
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Re: [Tagging] Spillways

[Richard]

On Wed, Mar 22, 2017 at 10:44:17AM +0900, John Willis wrote:
> How do you tag an emergency spillway? 
> 
> I am tagging a giant flood control reservoir in my region. The “lake” is 
> surrounded by giant man-made embankments on all sides, surrounded by an 
> additional  set of embankments, with gates to let the water out. There is no 
> dam per se, because there is ~200 km of this man-made 10-20m tall earthen 
> embankment (levee) around the entire river system - it is part of that. 

this is still a dam for me?

Richard

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Re: [Tagging] Spillways

[Tobias Wrede]

Hello,

actually, I have used
   warterway=spillway
   intermittent=yes
in the past, reasoning that this particular spillway 
(http://www.openstreetmap.org/way/451309286) is rarely put to use, while 
others might be more permanently flooded (regularly during high tides 
for example)


Tobias

Am 23.03.2017 um 12:58 schrieb John Sturdy:
I suppose  waterway=weir plus intermittent=yes would describe it, but 
I don't think that's as good as a specific spillway tag.


On Thu, Mar 23, 2017 at 6:52 AM, Andrew Harvey 
> wrote:


On 22 March 2017 at 16:56, Dave Swarthout > wrote:
> Weir does not seem appropriate for this type of thing. There is
a tag,
> waterway=spillway, that seems like a good fit - 81 uses so far.

I've seen these tagged as waterway=drain which is close but agree that
waterway=spillway is better. Would be great to have this documented on
the wiki.

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Re: [Tagging] Spillways

[John Willis]

Javbw
> On Mar 22, 2017, at 9:42 PM, Greg Troxel  wrote:
> 
> Also, presumably emergency spillways are mapped as areas, rather than
> lines, but they probably should have both, to have the water network and
> show the area.  The one I am familiar with is really large

OSM has a lot of objects originally represented by ways that eventually became 
possible to represent with areas - river+riverbank is a good example. 

I would like to: 

- document waterway=spillway. 

- create a spillway=(main/ secondary emergency) or similar sub-tag. 

- create a tag for mapping the extent of spillways.  (Waterway=spillway_area ?)

- create an area tag to go with dyke. (Man_made=dyke_area ? 

- Figure out how to map water control gates, the tiny hand-cranked vertical 
ones or the big sliding curved ones. 

Any feedback on these 5 points? 

Javbw. 


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Re: [Tagging] Spillways

[John Sturdy]

I suppose  waterway=weir plus intermittent=yes  would describe it, but I
don't think that's as good as a specific spillway tag.

On Thu, Mar 23, 2017 at 6:52 AM, Andrew Harvey 
wrote:

> On 22 March 2017 at 16:56, Dave Swarthout  wrote:
> > Weir does not seem appropriate for this type of thing. There is a tag,
> > waterway=spillway, that seems like a good fit - 81 uses so far.
>
> I've seen these tagged as waterway=drain which is close but agree that
> waterway=spillway is better. Would be great to have this documented on
> the wiki.
>
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Re: [Tagging] Spillways

[Andrew Harvey]

On 22 March 2017 at 16:56, Dave Swarthout  wrote:
> Weir does not seem appropriate for this type of thing. There is a tag,
> waterway=spillway, that seems like a good fit - 81 uses so far.

I've seen these tagged as waterway=drain which is close but agree that
waterway=spillway is better. Would be great to have this documented on
the wiki.

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Re: [Tagging] Spillways

[John Willis]

Ah yea, emergency=yes is bad.

3 questions: 

- mapping levees/dykes with additional area extent tags (like river+ riverbank) 

- mapping spillways in a similar fashion. 

- mapping levee control gates (buried in the levee) 

~~



Javbw
> On Mar 22, 2017, at 9:42 PM, Greg Troxel  wrote:
> 
> Also, presumably emergency spillways are mapped as areas, rather than
> lines,

What is interesting to me is that dykes (levees) are mapped as ways, though 
they can easily be mapped as areas. The levees around this system, about 10-15m 
tall and 40m wide are easily mappable from imagery and often have multiple ways 
that sit halfway up, on top, and transverse it, often all at once. 

If the minimum acceptable use is the way drawn on top of the levee, then there 
should be a tag similar to "riverbank" to map the extent of the levee to the 
sides. 

Maybe people are familiar with smaller dykes/levees, but I have never seen an 
entire 300km river system entirely encased in 10m levees before. And they are 
thinking of making the ones near the Tokyo Metro Area 20m. Mapping the area 
that such man-made structures extend from center seems like a no-brainer. 

I think the same would be true for a spillway - where the "top" of the spillway 
is, similar to the dyke tag, is probably the most important info, then it's 
area. 

Finally, wrapping up this tagging, of this levee system, there are hundreds of 
automatic/manual water control gates less than 1 meter wide to let streams and 
drains into the levee. There are about 100 larger 2-4m gates for larger streams 
and small rivers. 

Most of these small sized ones are buried in the dyke/levee, and the 
control structure built out from the side of the levee, sometimes with a little 
building on top to protect the mechanism for lowering/raising the gate, is a 
common occurrence. How would I tag such a feature? They are easily seen on 
aerial imagery.

https://goo.gl/maps/YKf3cMabUXn
The white structure is built to stabilize the control structure sticking up. 
The gate is buried in the levee and the exit can be seen near the water. The 
structure above is easily seen (some kind of building or man_made tag), and the 
valve/gate structure below  is easily mapped as a node on the waterway. There 
are hundreds and hundreds of these gates. 

Javbw 


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Re: [Tagging] Spillways

[Greg Troxel]

Martin Koppenhoefer  writes:

> sent from a phone
>
>> On 22 Mar 2017, at 09:15, Jean-Marc Liotier  wrote:
>> 
>> I answered too fast... Later in the thread John offers
>> waterway=spillway + emergency=yes + surface=* which seem even better
>> because it uses the generic emergency=yes instead of creating a new
>> spillway=emergency
>
>
> but emergency=yes is a legal access tag. Are there spillways that are
> used as roads? With spillway=emergency it is made explicit that this
> is a spillway category, not an access tag

Agreed. I was going to say that reusing emergency=yes was going to cause
trouble.

Also, presumably emergency spillways are mapped as areas, rather than
lines, but they probably should have both, to have the water network and
show the area.  The one I am familiar with is really large - the point
is to avoid erosion if it is ever used, to protect the dam from collapse
which might happen if the primary spillway overflowed.




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Re: [Tagging] Spillways

[Martin Koppenhoefer]

sent from a phone

> On 22 Mar 2017, at 09:15, Jean-Marc Liotier  wrote:
> 
> I answered too fast... Later in the thread John offers
> waterway=spillway + emergency=yes + surface=* which seem even better
> because it uses the generic emergency=yes instead of creating a new
> spillway=emergency


but emergency=yes is a legal access tag. Are there spillways that are used as 
roads? With spillway=emergency it is made explicit that this is a spillway 
category, not an access tag


cheers,
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Re: [Tagging] Spillways

[Jean-Marc Liotier]

On Wed, 22 Mar 2017 09:12:02 +0100
Jean-Marc Liotier  wrote:

> On Wed, 22 Mar 2017 12:56:49 +0700
> Dave Swarthout  wrote:
> >
> > You could also add emergency=yes to the above or create a new tag,
> > emergency=spillway  
> 
> waterway=spillway
> spillway=emergency
> 
> https://taginfo.openstreetmap.org/tags/waterway=spillway#overview

I answered too fast... Later in the thread John offers
waterway=spillway + emergency=yes + surface=* which seem even better
because it uses the generic emergency=yes instead of creating a new
spillway=emergency

spillway=* would only become preferable if a taxonomy of spillways
exists (such as main, secondary, emergency etc.)

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Re: [Tagging] Spillways

[Jean-Marc Liotier]

On Wed, 22 Mar 2017 12:56:49 +0700
Dave Swarthout  wrote:
>
> You could also add emergency=yes to the above or create a new tag,
> emergency=spillway

waterway=spillway
spillway=emergency

https://taginfo.openstreetmap.org/tags/waterway=spillway#overview

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Re: [Tagging] Spillways

[John Willis]

> On Mar 22, 2017, at 3:15 PM, Bill Ricker  wrote:
> 
> ​or use surface tags to distinguish the paved from unpaved​ as we do with 
> roads ?


This section is paved, but it is the function of the wall of dirt with asphalt 
on top I’m trying to map. 

someone actually took a picture out there in the winter.  
https://goo.gl/maps/QfrZfUiVze22  

The old way (beyond the gate) disappears, as the top of the old levee was 
removed, lowering it by 3-5m. https://goo.gl/maps/bTdcVV6H9pn 
 . This is covered by asphalt (to protect 
against erosion), and it is an embankment (holding back water during flooding), 
but it’s function is a spillway. the river to the right is the path to the sea. 
The entire inner reservoir (way off to the left) has concrete walls. Wether is 
is concrete, asphalt, or earth, it could be a dam, a spillway (with/without 
control gates), or an emergency spillway, if the normal one is in danger of 
being overtopped. in this case, the emergency spillways protect the gates to 
the south and the homes to the west. if you pan the photo 180 degrees (look 
behind “you”), you can see the gates it is protecting. 


The dam and a weir have the same job - to hold back water. a weir usually holds 
back water to feed into a pipe or some other use for the water, as a dam does, 
but is designed to be overtopped. it is often submerged, being overtopped, 
while doing it’s main function of routing water into a pipe or making a lake or 
similar.
a spillway's sole job is to get rid of excess water, for the safety or planning 
the use of the dam’s capacity. it is a feature of the dam (or other water 
control system), not the main feature itself. in this case, the spillway is a 
part of the levee system.

waterway=spillway + emergency=yes, + surface=* as the spillway is for 
emergencies seems appropriate. 

Thanks for the feedback. 

Javbw

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Re: [Tagging] Spillways

[Bill Ricker]

On Wed, Mar 22, 2017 at 1:56 AM, Dave Swarthout 
wrote:

> Weir does not seem appropriate for this type of thing. There is a tag,
> waterway=spillway, that seems like a good fit - 81 uses so far.
>
> You could also add emergency=yes to the above or create a new tag,
> emergency=spillway
>

​or use surface tags to distinguish the paved from unpaved​ as we do with
roads ?



-- 
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bill.n1...@gmail.com
https://www.linkedin.com/in/n1vux
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Re: [Tagging] Spillways

[Dave Swarthout]

Weir does not seem appropriate for this type of thing. There is a tag,
waterway=spillway, that seems like a good fit - 81 uses so far.

You could also add emergency=yes to the above or create a new tag,
emergency=spillway

Cheers

Dave

On Wed, Mar 22, 2017 at 12:25 PM, Mark Wagner  wrote:

> On Wed, 22 Mar 2017 10:44:17 +0900
> John Willis  wrote:
>
> > How do you tag an emergency spillway?
> >
> > I am tagging a giant flood control reservoir in my region. The “lake”
> > is surrounded by giant man-made embankments on all sides, surrounded
> > by an additional  set of embankments, with gates to let the water
> > out. There is no dam per se, because there is ~200 km of this
> > man-made 10-20m tall earthen embankment (levee) around the entire
> > river system - it is part of that.
> >
> > When this levee system fails uncontrollably (like it did downstream
> > from me in 2015), it is really bad.
> > https://www.youtube.com/watch?v=Hfs3OeqiqRk
> > 
> >
> > This reservoir system catches water during a typhoon from a smaller
> > river, then releases it slowly after the peak flooding into the
> > larger river. this reduces the chance of flooding further
> > downstream.
> >
> > However, it has 2 sets of emergency spillways (each about 1Km long)
> > to let water out of both sets of embankments, so where it “fails" can
> > be controlled. it is 5 m lower than rest of the embankments
> > surrounding the reservoirs. These were recently added.
> >
> > I made a polygon on one such spillway.
> > https://www.openstreetmap.org/way/481898093#map=14/36.2115/139.6880
> >  .
> > the heart-shaped lake is the reservoir, and most of the surrounding
> > green areas are part of the flood control basin made by the second
> > set of levees.
> >
> > These *emergency* spillways are considered safety features of most
> > large water control projects - if the human-controlled gates o the
> > normal spillway jam shut, the emergency spillways will keep the
> > dam/embankments from being over-topped in unexpected places. I know
> > these are a major mappable feature of large dams, but they are not
> > mentioned on the Dam wiki page. Maybe I am looking at it wrong.
> >
> > As these are not a weir, nor a normal path for water to go, I
> > wouldn’t tag them as a weir nor as a object normally associated with
> > a waterway line running through it.
> >
> > is there an existing tag or another name for these features that I
> > don’t know of? How do I tag these emergency spillways (and heck -
> > these huge levee embankments!) correctly?
>
> For what it's worth, Oroville Dam
> (https://www.openstreetmap.org/#map=17/39.54412/-121.49263) currently
> has its emergency spillway tagged as a weir.
>
> --
> Mark
>
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Chiang Mai, Thailand
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Re: [Tagging] Spillways

[Mark Wagner]

On Wed, 22 Mar 2017 10:44:17 +0900
John Willis  wrote:

> How do you tag an emergency spillway? 
> 
> I am tagging a giant flood control reservoir in my region. The “lake”
> is surrounded by giant man-made embankments on all sides, surrounded
> by an additional  set of embankments, with gates to let the water
> out. There is no dam per se, because there is ~200 km of this
> man-made 10-20m tall earthen embankment (levee) around the entire
> river system - it is part of that. 
> 
> When this levee system fails uncontrollably (like it did downstream
> from me in 2015), it is really bad.
> https://www.youtube.com/watch?v=Hfs3OeqiqRk
>  
> 
> This reservoir system catches water during a typhoon from a smaller
> river, then releases it slowly after the peak flooding into the
> larger river. this reduces the chance of flooding further
> downstream.  
> 
> However, it has 2 sets of emergency spillways (each about 1Km long)
> to let water out of both sets of embankments, so where it “fails" can
> be controlled. it is 5 m lower than rest of the embankments
> surrounding the reservoirs. These were recently added. 
> 
> I made a polygon on one such spillway.
> https://www.openstreetmap.org/way/481898093#map=14/36.2115/139.6880
>  .
> the heart-shaped lake is the reservoir, and most of the surrounding
> green areas are part of the flood control basin made by the second
> set of levees. 
> 
> These *emergency* spillways are considered safety features of most
> large water control projects - if the human-controlled gates o the
> normal spillway jam shut, the emergency spillways will keep the
> dam/embankments from being over-topped in unexpected places. I know
> these are a major mappable feature of large dams, but they are not
> mentioned on the Dam wiki page. Maybe I am looking at it wrong. 
> 
> As these are not a weir, nor a normal path for water to go, I
> wouldn’t tag them as a weir nor as a object normally associated with
> a waterway line running through it. 
> 
> is there an existing tag or another name for these features that I
> don’t know of? How do I tag these emergency spillways (and heck -
> these huge levee embankments!) correctly? 

For what it's worth, Oroville Dam
(https://www.openstreetmap.org/#map=17/39.54412/-121.49263) currently
has its emergency spillway tagged as a weir.

-- 
Mark

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[Tagging] Spillways

[John Willis]

How do you tag an emergency spillway? 

I am tagging a giant flood control reservoir in my region. The “lake” is 
surrounded by giant man-made embankments on all sides, surrounded by an 
additional  set of embankments, with gates to let the water out. There is no 
dam per se, because there is ~200 km of this man-made 10-20m tall earthen 
embankment (levee) around the entire river system - it is part of that. 

When this levee system fails uncontrollably (like it did downstream from me in 
2015), it is really bad. https://www.youtube.com/watch?v=Hfs3OeqiqRk 
 

This reservoir system catches water during a typhoon from a smaller river, then 
releases it slowly after the peak flooding into the larger river. this reduces 
the chance of flooding further downstream.  

However, it has 2 sets of emergency spillways (each about 1Km long) to let 
water out of both sets of embankments, so where it “fails" can be controlled. 
it is 5 m lower than rest of the embankments surrounding the reservoirs. These 
were recently added. 

I made a polygon on one such spillway. 
https://www.openstreetmap.org/way/481898093#map=14/36.2115/139.6880 
 . the 
heart-shaped lake is the reservoir, and most of the surrounding green areas are 
part of the flood control basin made by the second set of levees. 

These *emergency* spillways are considered safety features of most large water 
control projects - if the human-controlled gates o the normal spillway jam 
shut, the emergency spillways will keep the dam/embankments from being 
over-topped in unexpected places. I know these are a major mappable feature of 
large dams, but they are not mentioned on the Dam wiki page. Maybe I am looking 
at it wrong. 

As these are not a weir, nor a normal path for water to go, I wouldn’t tag them 
as a weir nor as a object normally associated with a waterway line running 
through it. 

is there an existing tag or another name for these features that I don’t know 
of? How do I tag these emergency spillways (and heck - these huge levee 
embankments!) correctly? 

Javbw___
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